A microwave determination of some molecular parameters for HCO

Abstract

The weak F=3→F=2, J=5/2 hyperfine component of the 2₁₁-2₁₂ K-doubling transition in HCO has been detected and its frequency measured (8846·0±0·5 MHz). A combination of this frequency with previously measured frequencies leads to an improved set of molecular parameters for HCO. Where possible, the values for the parameters are compared with those obtained from solid-state studies of HCO and the proton hyperfine parameters are interpreted in terms of the electronic structure of the [Xtilde]²A′ state.